Hydrocarbons may be produced from well bores drilled from the surface through a variety of producing and non-producing formations. The well bore may be drilled substantially vertically or may be an offset well that is not vertical and has some amount of horizontal displacement from the surface entry point. In some cases, a multilateral well may be drilled comprising a plurality of wellbores drilled off of a main wellbore, each of which may be referred to as a lateral wellbore. Portions of lateral wellbores may be substantially horizontal to the surface. In some provinces, wellbores may be very deep, for example extending more than 10,000 feet from the surface.
In the servicing of an oil or gas well bore, straddle systems may be used, for example, as a downhole tool for performing fracture testing or fracture diagnostic testing on a formation proximate to the well bore, as well as for fracture treatments, chemical applications or a variety of other services. These assemblies typically include an upper packer or seal, a lower packer or seal and one or more tools, such as a hydraulic fracturing sub, that are situated between the upper and lower packers, are coupled thereto and, thus, “straddle” a gap between the packers. To perform downhole fracture testing, a straddle system is run into the well bore on a work string, the corresponding lower and upper packers are set and the gap in the well bore between the packers is pressurized, for example, by pumping a fluid down the work string and through a fracture port situated in the straddle system.